Frictional lining extruding apparatus and method



K. PFEIFFER July 11, 1933.

FRICTIONAL LINING EXTRUDING APPARATUS AND METHOD Filed 001:. 25. 1930 INVENTOR KARL PF'E/FFER.

ATTORNEY Patented July 11, 1933 UNITED STATES KARL PFEIFFER, OF HIGHLAND PARK, MICHIGAN, ASSIGNQR T0 CHRYSLER OGRPORA- TION, OF DETRUIT, MICHIGAN, A CORPORATION OF DELAXVABE 7 FRICTIONAL LINING EXTBUDING APPARATUS AND METHOD Application. filed October 25, 1930. Serial No. 491,300.

This invention relates to an improved method and apparatus for extruding lining material, particularly frictional clutch lining having different coefficients of friction at spaced areas.

The main objects of the invention are to provide apparatus for simultaneously eX- truding ribbons of frictional material having dili'erent coefiicients of. friction; to provide apparatus of this kind which has a discharge nozzle that brings the ribbons together and intermingles their materials at their adjacent edge portions forming an in tegral member; to provide extruding apparatus which is adapted to deposit a strip of integrally connected ribbons of frictional lining material directly into a recess of a die part in which the lining is ultimately formed under compression; and to provide an improved method for shaping the extruded material to the contour of the recess of the die part in which it is received.

An illustrative embodiment of my invention is shown in the accompanying drawing, in which:

Fig. 1 is a plan View, partly in section, diagrammatically showing an extruding apparatus which embodies my invention.

Fig. 2 is a fragmentary section of the die part by which the lining is ultimately formed illustrating a compressing operation.

Fig. 3 is a transverse section of the nozzle taken on the line 2-2 of Fig. 1.

Fig. 1 is a plan view of a clutch disc having lining formed by my improved method secured on one side face.

In frictional members, such as clutch discs, it has been found to be desirable to have the coeiiicient of friction of the working surface of the discs vary so that the areas thereof which are located in close proximity to the center of the disc have a higher coefficient of friction than those at the outermost portions of the discs. Extruded materials having dif ferent compositions and correspondingly dif ferent coefficients of friction may be success fully moulded under pressure to the shape of a disc and used in clutches.

The structure shown diagrammatically in the drawing illustrates an improved appa ratus for extruding materials for frictional discs of the type which vary in frictional properties at their inner and outer portions. This apparatus, for the purpose of illustration, three extruding units 1, 2 and 3 3 which include cylinders 4, 5 and 6 in which pistons 7 8 and 9 are provided. The pistons 7, 8 and 9 are mounted on threaded stems or piston rods 10, 11 and 12, respectively which are threaded centrally through meshedsi pinions 13, 1e and 15. Each pinion has a hub part 16 which is journaled in an aperture of a cap 17 located on the open end of each cylinder. The external teeth of the pinions are meshed with each other and with a 16 driving pinion 18.

Communicating with the closed ends of the cylinders 41, 5 and dare discharge ducts 19,. 20 and 21, respectively, which converge at their outer ends and which extend into a com-' mon nozzle 22. The nozzle 22 has a constricted outlet 23 which is smallerin area than the combined areas of the outlets of the ducts 19, 20 and 21.

A die part 2 1 having an annular groove is provided for receiving the extruded material which is discharged from the nozzle 22. This die part is preferably supported at its center upon a pivot 26 with the nozzle 22 in registration with the groove 25 so that when 3 the material is ejected from the nozzle, the die part 2st may be rotated causing the material to conform with the shape of the groove. The pinion 15 is larger than the pinion 1 1 which in turn is larger than. the pinion 13.

In operation, the pistons 7, 8 and 9 are simultaneously driven into the cylinders 1, 5 and 6 at different rates. As the pinion 13 is smaller than the pinion 1 1 which in turn is smaller than the pinion 15, the piston 7 is 96 moved inwardly at a greater rate than the piston S which is moved inwardly at a greate rate than the piston 9. The cylinders 7 8 and 9 are each filled with plastic compositions having a frictional ingredient such as 9 asbestos in various percentages. The asbes-v tos is mixed in a suitable binder such as rubber, and if. desired, graphite may also be included in the con position. The charge in the cylinder 6 has a greater percentage ofthe frictional element than the charge of the cylinder 5 which in turn has a greater percentage of the frictional element than the charge of the cylinder 4.

During inward movement of the pistons, the materials of the cylinders are forced through the ducts 19, 20 and 21 and into the nozzle 22 wherein the materials from the respective ducts are forced together sufficiently to commingle their adjacent side edges, thus forming an integral strip comprising materials of three different compositions as illustrated on the left side of Fig. 2.

After the material leaves the nozzle 22, it is received in the groove 25 of the die part 24 which is rotated about a central axis. \Vhen the groove is filled, the die part is placed upon the bed 27 of a press and it is subjected to compression by a tubular element 28. I11 this operation, the material is reduced in thickness from the thickness shown at the left in Fig. 2 to that shown at the right in Fig. 2. The annular disc or ring 29 formed by this method is integral throughout and may be conveniently secured to a face of a clutch disc 30 by rivets 31, as shown in Fig. 4.

Although but one specific embodiment of this invention has herein been shown and described, it will be understood that various changes in the size, shape and arrangement of parts may be made without departing from the spirit of my invention and it is not my intention to limit its scope other than by the terms of the appended claims.

What I claim is:

1. In extruding apparatus, a plurality of ejectors, discharge conduits, one leading from each ejector, a common nozzle communicatingwith the discharge ends of all of said conduits, and mechanism for simultaneously operating said ejectors at respectively dif ferent rates so as to discharge different quantities of materials.

2. In extruding apparatus, a plurality of ejecting units each adapted to discharge material at a different rate, a plurality of discharge ducts, one communicating with each ejecting unit, and a common nozzle communithe materials discharged from said ejectors together so as to commingle the material thereof at said edge portions and to form an integral product.

4. The method of manufacturing frictional lining discs which consists in simultanei ously ejecting strips of frictional material having different coefficients of friction through a restricted passage so as to join their adjacent edges, receiving the discharge of said passage upon a rotating die part with the strip having the greatest coefiicient of frictionlocated closest to the axis of rotation of said die part, and compressing the integrally joined strips on said die part.

5. The method of manufacturing frictional lining discs which consists in simultaneously ejecting a plurality of strips of material having different compositions at diverse rates through a restricted passage so as to integrally join their adjacent edges, receiving the discharge from said passage on a rotating die part with the strip having the lowest discharge rate located closest to the axis of rotation of said-die part, and compressing the integrally oined strips on said die part.

KARL PFEIFFER. 

